summaryrefslogtreecommitdiffstats
path: root/Source/cmLocalNinjaGenerator.cxx
blob: a8647b189b82ae3c7f3a743c08f488ec52ba007e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
   file Copyright.txt or https://cmake.org/licensing for details.  */
#include "cmLocalNinjaGenerator.h"

#include <algorithm>
#include <assert.h>
#include <iterator>
#include <memory> // IWYU pragma: keep
#include <sstream>
#include <stdio.h>
#include <utility>

#include "cmCryptoHash.h"
#include "cmCustomCommand.h"
#include "cmCustomCommandGenerator.h"
#include "cmGeneratedFileStream.h"
#include "cmGeneratorTarget.h"
#include "cmGlobalGenerator.h"
#include "cmGlobalNinjaGenerator.h"
#include "cmLocalGenerator.h"
#include "cmMakefile.h"
#include "cmNinjaTargetGenerator.h"
#include "cmRulePlaceholderExpander.h"
#include "cmSourceFile.h"
#include "cmState.h"
#include "cmStateTypes.h"
#include "cmSystemTools.h"
#include "cmake.h"
#include "cmsys/FStream.hxx"

cmLocalNinjaGenerator::cmLocalNinjaGenerator(cmGlobalGenerator* gg,
                                             cmMakefile* mf)
  : cmLocalCommonGenerator(gg, mf, mf->GetState()->GetBinaryDirectory())
  , HomeRelativeOutputPath("")
{
}

// Virtual public methods.

cmRulePlaceholderExpander*
cmLocalNinjaGenerator::CreateRulePlaceholderExpander() const
{
  cmRulePlaceholderExpander* ret =
    this->cmLocalGenerator::CreateRulePlaceholderExpander();
  ret->SetTargetImpLib("$TARGET_IMPLIB");
  return ret;
}

cmLocalNinjaGenerator::~cmLocalNinjaGenerator()
{
}

void cmLocalNinjaGenerator::Generate()
{
  // Compute the path to use when referencing the current output
  // directory from the top output directory.
  this->HomeRelativeOutputPath = this->ConvertToRelativePath(
    this->GetBinaryDirectory(), this->GetCurrentBinaryDirectory());
  if (this->HomeRelativeOutputPath == ".") {
    this->HomeRelativeOutputPath.clear();
  }

  this->WriteProcessedMakefile(this->GetBuildFileStream());
#ifdef NINJA_GEN_VERBOSE_FILES
  this->WriteProcessedMakefile(this->GetRulesFileStream());
#endif

  // We do that only once for the top CMakeLists.txt file.
  if (this->IsRootMakefile()) {
    this->WriteBuildFileTop();

    this->WritePools(this->GetRulesFileStream());

    const std::string showIncludesPrefix =
      this->GetMakefile()->GetSafeDefinition("CMAKE_CL_SHOWINCLUDES_PREFIX");
    if (!showIncludesPrefix.empty()) {
      cmGlobalNinjaGenerator::WriteComment(this->GetRulesFileStream(),
                                           "localized /showIncludes string");
      this->GetRulesFileStream()
        << "msvc_deps_prefix = " << showIncludesPrefix << "\n\n";
    }
  }

  const std::vector<cmGeneratorTarget*>& targets = this->GetGeneratorTargets();
  for (cmGeneratorTarget* target : targets) {
    if (target->GetType() == cmStateEnums::INTERFACE_LIBRARY) {
      continue;
    }
    cmNinjaTargetGenerator* tg = cmNinjaTargetGenerator::New(target);
    if (tg) {
      tg->Generate();
      // Add the target to "all" if required.
      if (!this->GetGlobalNinjaGenerator()->IsExcluded(
            this->GetGlobalNinjaGenerator()->GetLocalGenerators()[0],
            target)) {
        this->GetGlobalNinjaGenerator()->AddDependencyToAll(target);
      }
      delete tg;
    }
  }

  this->WriteCustomCommandBuildStatements();
}

// TODO: Picked up from cmLocalUnixMakefileGenerator3.  Refactor it.
std::string cmLocalNinjaGenerator::GetTargetDirectory(
  cmGeneratorTarget const* target) const
{
  std::string dir = cmake::GetCMakeFilesDirectoryPostSlash();
  dir += target->GetName();
#if defined(__VMS)
  dir += "_dir";
#else
  dir += ".dir";
#endif
  return dir;
}

// Non-virtual public methods.

const cmGlobalNinjaGenerator* cmLocalNinjaGenerator::GetGlobalNinjaGenerator()
  const
{
  return static_cast<const cmGlobalNinjaGenerator*>(
    this->GetGlobalGenerator());
}

cmGlobalNinjaGenerator* cmLocalNinjaGenerator::GetGlobalNinjaGenerator()
{
  return static_cast<cmGlobalNinjaGenerator*>(this->GetGlobalGenerator());
}

// Virtual protected methods.

std::string cmLocalNinjaGenerator::ConvertToIncludeReference(
  std::string const& path, cmOutputConverter::OutputFormat format,
  bool forceFullPaths)
{
  if (forceFullPaths) {
    return this->ConvertToOutputFormat(cmSystemTools::CollapseFullPath(path),
                                       format);
  }
  return this->ConvertToOutputFormat(
    this->ConvertToRelativePath(this->GetBinaryDirectory(), path), format);
}

// Private methods.

cmGeneratedFileStream& cmLocalNinjaGenerator::GetBuildFileStream() const
{
  return *this->GetGlobalNinjaGenerator()->GetBuildFileStream();
}

cmGeneratedFileStream& cmLocalNinjaGenerator::GetRulesFileStream() const
{
  return *this->GetGlobalNinjaGenerator()->GetRulesFileStream();
}

const cmake* cmLocalNinjaGenerator::GetCMakeInstance() const
{
  return this->GetGlobalGenerator()->GetCMakeInstance();
}

cmake* cmLocalNinjaGenerator::GetCMakeInstance()
{
  return this->GetGlobalGenerator()->GetCMakeInstance();
}

void cmLocalNinjaGenerator::WriteBuildFileTop()
{
  // For the build file.
  this->WriteProjectHeader(this->GetBuildFileStream());
  this->WriteNinjaRequiredVersion(this->GetBuildFileStream());
  this->WriteNinjaFilesInclusion(this->GetBuildFileStream());

  // For the rule file.
  this->WriteProjectHeader(this->GetRulesFileStream());
}

void cmLocalNinjaGenerator::WriteProjectHeader(std::ostream& os)
{
  cmGlobalNinjaGenerator::WriteDivider(os);
  os << "# Project: " << this->GetProjectName() << std::endl
     << "# Configuration: " << this->ConfigName << std::endl;
  cmGlobalNinjaGenerator::WriteDivider(os);
}

void cmLocalNinjaGenerator::WriteNinjaRequiredVersion(std::ostream& os)
{
  // Default required version
  std::string requiredVersion = cmGlobalNinjaGenerator::RequiredNinjaVersion();

  // Ninja generator uses the 'console' pool if available (>= 1.5)
  if (this->GetGlobalNinjaGenerator()->SupportsConsolePool()) {
    requiredVersion =
      cmGlobalNinjaGenerator::RequiredNinjaVersionForConsolePool();
  }

  // The Ninja generator writes rules which require support for restat
  // when rebuilding build.ninja manifest (>= 1.8)
  if (this->GetGlobalNinjaGenerator()->SupportsManifestRestat() &&
      this->GetCMakeInstance()->DoWriteGlobVerifyTarget() &&
      !this->GetGlobalNinjaGenerator()->GlobalSettingIsOn(
        "CMAKE_SUPPRESS_REGENERATION")) {
    requiredVersion =
      cmGlobalNinjaGenerator::RequiredNinjaVersionForManifestRestat();
  }

  cmGlobalNinjaGenerator::WriteComment(
    os, "Minimal version of Ninja required by this file");
  os << "ninja_required_version = " << requiredVersion << std::endl
     << std::endl;
}

void cmLocalNinjaGenerator::WritePools(std::ostream& os)
{
  cmGlobalNinjaGenerator::WriteDivider(os);

  const char* jobpools =
    this->GetCMakeInstance()->GetState()->GetGlobalProperty("JOB_POOLS");
  if (!jobpools) {
    jobpools = this->GetMakefile()->GetDefinition("CMAKE_JOB_POOLS");
  }
  if (jobpools) {
    cmGlobalNinjaGenerator::WriteComment(
      os, "Pools defined by global property JOB_POOLS");
    std::vector<std::string> pools;
    cmSystemTools::ExpandListArgument(jobpools, pools);
    for (std::string const& pool : pools) {
      const std::string::size_type eq = pool.find('=');
      unsigned int jobs;
      if (eq != std::string::npos &&
          sscanf(pool.c_str() + eq, "=%u", &jobs) == 1) {
        os << "pool " << pool.substr(0, eq) << std::endl;
        os << "  depth = " << jobs << std::endl;
        os << std::endl;
      } else {
        cmSystemTools::Error("Invalid pool defined by property 'JOB_POOLS': ",
                             pool.c_str());
      }
    }
  }
}

void cmLocalNinjaGenerator::WriteNinjaFilesInclusion(std::ostream& os)
{
  cmGlobalNinjaGenerator::WriteDivider(os);
  os << "# Include auxiliary files.\n"
     << "\n";
  cmGlobalNinjaGenerator* ng = this->GetGlobalNinjaGenerator();
  std::string const ninjaRulesFile =
    ng->NinjaOutputPath(cmGlobalNinjaGenerator::NINJA_RULES_FILE);
  std::string const rulesFilePath = ng->EncodePath(ninjaRulesFile);
  cmGlobalNinjaGenerator::WriteInclude(os, rulesFilePath,
                                       "Include rules file.");
  os << "\n";
}

void cmLocalNinjaGenerator::WriteProcessedMakefile(std::ostream& os)
{
  cmGlobalNinjaGenerator::WriteDivider(os);
  os << "# Write statements declared in CMakeLists.txt:" << std::endl
     << "# " << this->Makefile->GetDefinition("CMAKE_CURRENT_LIST_FILE")
     << std::endl;
  if (this->IsRootMakefile()) {
    os << "# Which is the root file." << std::endl;
  }
  cmGlobalNinjaGenerator::WriteDivider(os);
  os << std::endl;
}

void cmLocalNinjaGenerator::AppendTargetOutputs(cmGeneratorTarget* target,
                                                cmNinjaDeps& outputs)
{
  this->GetGlobalNinjaGenerator()->AppendTargetOutputs(target, outputs);
}

void cmLocalNinjaGenerator::AppendTargetDepends(cmGeneratorTarget* target,
                                                cmNinjaDeps& outputs,
                                                cmNinjaTargetDepends depends)
{
  this->GetGlobalNinjaGenerator()->AppendTargetDepends(target, outputs,
                                                       depends);
}

void cmLocalNinjaGenerator::AppendCustomCommandDeps(
  cmCustomCommandGenerator const& ccg, cmNinjaDeps& ninjaDeps)
{
  const std::vector<std::string>& deps = ccg.GetDepends();
  for (std::string const& i : deps) {
    std::string dep;
    if (this->GetRealDependency(i, this->GetConfigName(), dep)) {
      ninjaDeps.push_back(
        this->GetGlobalNinjaGenerator()->ConvertToNinjaPath(dep));
    }
  }
}

std::string cmLocalNinjaGenerator::WriteCommandScript(
  std::vector<std::string> const& cmdLines, std::string const& customStep,
  cmGeneratorTarget const* target) const
{
  std::string scriptPath;
  if (target) {
    scriptPath = target->GetSupportDirectory();
  } else {
    scriptPath = this->GetCurrentBinaryDirectory();
    scriptPath += cmake::GetCMakeFilesDirectory();
  }
  cmSystemTools::MakeDirectory(scriptPath);
  scriptPath += '/';
  scriptPath += customStep;
#ifdef _WIN32
  scriptPath += ".bat";
#else
  scriptPath += ".sh";
#endif

  cmsys::ofstream script(scriptPath.c_str());

#ifdef _WIN32
  script << "@echo off\n";
  int line = 1;
#else
  script << "set -e\n\n";
#endif

  for (auto const& i : cmdLines) {
    std::string cmd = i;
    // The command line was built assuming it would be written to
    // the build.ninja file, so it uses '$$' for '$'.  Remove this
    // for the raw shell script.
    cmSystemTools::ReplaceString(cmd, "$$", "$");
#ifdef _WIN32
    script << cmd << " || (set FAIL_LINE=" << ++line << "& goto :ABORT)"
           << '\n';
#else
    script << cmd << '\n';
#endif
  }

#ifdef _WIN32
  script << "goto :EOF\n\n"
            ":ABORT\n"
            "set ERROR_CODE=%ERRORLEVEL%\n"
            "echo Batch file failed at line %FAIL_LINE% "
            "with errorcode %ERRORLEVEL%\n"
            "exit /b %ERROR_CODE%";
#endif

  return scriptPath;
}

std::string cmLocalNinjaGenerator::BuildCommandLine(
  std::vector<std::string> const& cmdLines, std::string const& customStep,
  cmGeneratorTarget const* target) const
{
  // If we have no commands but we need to build a command anyway, use noop.
  // This happens when building a POST_BUILD value for link targets that
  // don't use POST_BUILD.
  if (cmdLines.empty()) {
    return cmGlobalNinjaGenerator::SHELL_NOOP;
  }

  // If this is a custom step then we will have no '$VAR' ninja placeholders.
  // This means we can deal with long command sequences by writing to a script.
  // Do this if the command lines are on the scale of the OS limit.
  if (!customStep.empty()) {
    size_t cmdLinesTotal = 0;
    for (std::string const& cmd : cmdLines) {
      cmdLinesTotal += cmd.length() + 6;
    }
    if (cmdLinesTotal > cmSystemTools::CalculateCommandLineLengthLimit() / 2) {
      std::string const scriptPath =
        this->WriteCommandScript(cmdLines, customStep, target);
      std::string cmd
#ifndef _WIN32
        = "/bin/sh "
#endif
        ;
      cmd += this->ConvertToOutputFormat(
        this->GetGlobalNinjaGenerator()->ConvertToNinjaPath(scriptPath),
        cmOutputConverter::SHELL);

      // Add an unused argument based on script content so that Ninja
      // knows when the command lines change.
      cmd += " ";
      cmCryptoHash hash(cmCryptoHash::AlgoSHA256);
      cmd += hash.HashFile(scriptPath).substr(0, 16);
      return cmd;
    }
  }

  std::ostringstream cmd;
  for (std::vector<std::string>::const_iterator li = cmdLines.begin();
       li != cmdLines.end(); ++li)
#ifdef _WIN32
  {
    if (li != cmdLines.begin()) {
      cmd << " && ";
    } else if (cmdLines.size() > 1) {
      cmd << "cmd.exe /C \"";
    }
    // Put current cmdLine in brackets if it contains "||" because it has
    // higher precedence than "&&" in cmd.exe
    if (li->find("||") != std::string::npos) {
      cmd << "( " << *li << " )";
    } else {
      cmd << *li;
    }
  }
  if (cmdLines.size() > 1) {
    cmd << "\"";
  }
#else
  {
    if (li != cmdLines.begin()) {
      cmd << " && ";
    }
    cmd << *li;
  }
#endif
  return cmd.str();
}

void cmLocalNinjaGenerator::AppendCustomCommandLines(
  cmCustomCommandGenerator const& ccg, std::vector<std::string>& cmdLines)
{
  if (ccg.GetNumberOfCommands() > 0) {
    std::string wd = ccg.GetWorkingDirectory();
    if (wd.empty()) {
      wd = this->GetCurrentBinaryDirectory();
    }

    std::ostringstream cdCmd;
#ifdef _WIN32
    std::string cdStr = "cd /D ";
#else
    std::string cdStr = "cd ";
#endif
    cdCmd << cdStr
          << this->ConvertToOutputFormat(wd, cmOutputConverter::SHELL);
    cmdLines.push_back(cdCmd.str());
  }

  std::string launcher = this->MakeCustomLauncher(ccg);

  for (unsigned i = 0; i != ccg.GetNumberOfCommands(); ++i) {
    cmdLines.push_back(launcher +
                       this->ConvertToOutputFormat(ccg.GetCommand(i),
                                                   cmOutputConverter::SHELL));

    std::string& cmd = cmdLines.back();
    ccg.AppendArguments(i, cmd);
  }
}

void cmLocalNinjaGenerator::WriteCustomCommandBuildStatement(
  cmCustomCommand const* cc, const cmNinjaDeps& orderOnlyDeps)
{
  if (this->GetGlobalNinjaGenerator()->SeenCustomCommand(cc)) {
    return;
  }

  cmCustomCommandGenerator ccg(*cc, this->GetConfigName(), this);

  const std::vector<std::string>& outputs = ccg.GetOutputs();
  const std::vector<std::string>& byproducts = ccg.GetByproducts();
  cmNinjaDeps ninjaOutputs(outputs.size() + byproducts.size()), ninjaDeps;

  bool symbolic = false;
  for (std::vector<std::string>::const_iterator o = outputs.begin();
       !symbolic && o != outputs.end(); ++o) {
    if (cmSourceFile* sf = this->Makefile->GetSource(*o)) {
      symbolic = sf->GetPropertyAsBool("SYMBOLIC");
    }
  }

#if 0
#  error TODO: Once CC in an ExternalProject target must provide the \
    file of each imported target that has an add_dependencies pointing \
    at us.  How to know which ExternalProject step actually provides it?
#endif
  std::transform(outputs.begin(), outputs.end(), ninjaOutputs.begin(),
                 this->GetGlobalNinjaGenerator()->MapToNinjaPath());
  std::transform(byproducts.begin(), byproducts.end(),
                 ninjaOutputs.begin() + outputs.size(),
                 this->GetGlobalNinjaGenerator()->MapToNinjaPath());
  this->AppendCustomCommandDeps(ccg, ninjaDeps);

  for (std::string const& ninjaOutput : ninjaOutputs) {
    this->GetGlobalNinjaGenerator()->SeenCustomCommandOutput(ninjaOutput);
  }

  std::vector<std::string> cmdLines;
  this->AppendCustomCommandLines(ccg, cmdLines);

  if (cmdLines.empty()) {
    this->GetGlobalNinjaGenerator()->WritePhonyBuild(
      this->GetBuildFileStream(),
      "Phony custom command for " + ninjaOutputs[0], ninjaOutputs, ninjaDeps,
      cmNinjaDeps(), orderOnlyDeps, cmNinjaVars());
  } else {
    std::string customStep = cmSystemTools::GetFilenameName(ninjaOutputs[0]);
    // Hash full path to make unique.
    customStep += '-';
    cmCryptoHash hash(cmCryptoHash::AlgoSHA256);
    customStep += hash.HashString(ninjaOutputs[0]).substr(0, 7);

    this->GetGlobalNinjaGenerator()->WriteCustomCommandBuild(
      this->BuildCommandLine(cmdLines, customStep),
      this->ConstructComment(ccg), "Custom command for " + ninjaOutputs[0],
      cc->GetDepfile(), cc->GetUsesTerminal(),
      /*restat*/ !symbolic || !byproducts.empty(), ninjaOutputs, ninjaDeps,
      orderOnlyDeps);
  }
}

void cmLocalNinjaGenerator::AddCustomCommandTarget(cmCustomCommand const* cc,
                                                   cmGeneratorTarget* target)
{
  CustomCommandTargetMap::value_type v(cc, std::set<cmGeneratorTarget*>());
  std::pair<CustomCommandTargetMap::iterator, bool> ins =
    this->CustomCommandTargets.insert(v);
  if (ins.second) {
    this->CustomCommands.push_back(cc);
  }
  ins.first->second.insert(target);
}

void cmLocalNinjaGenerator::WriteCustomCommandBuildStatements()
{
  for (cmCustomCommand const* customCommand : this->CustomCommands) {
    CustomCommandTargetMap::iterator i =
      this->CustomCommandTargets.find(customCommand);
    assert(i != this->CustomCommandTargets.end());

    // A custom command may appear on multiple targets.  However, some build
    // systems exist where the target dependencies on some of the targets are
    // overspecified, leading to a dependency cycle.  If we assume all target
    // dependencies are a superset of the true target dependencies for this
    // custom command, we can take the set intersection of all target
    // dependencies to obtain a correct dependency list.
    //
    // FIXME: This won't work in certain obscure scenarios involving indirect
    // dependencies.
    std::set<cmGeneratorTarget*>::iterator j = i->second.begin();
    assert(j != i->second.end());
    std::vector<std::string> ccTargetDeps;
    this->GetGlobalNinjaGenerator()->AppendTargetDependsClosure(*j,
                                                                ccTargetDeps);
    std::sort(ccTargetDeps.begin(), ccTargetDeps.end());
    ++j;

    for (; j != i->second.end(); ++j) {
      std::vector<std::string> jDeps, depsIntersection;
      this->GetGlobalNinjaGenerator()->AppendTargetDependsClosure(*j, jDeps);
      std::sort(jDeps.begin(), jDeps.end());
      std::set_intersection(ccTargetDeps.begin(), ccTargetDeps.end(),
                            jDeps.begin(), jDeps.end(),
                            std::back_inserter(depsIntersection));
      ccTargetDeps = depsIntersection;
    }

    this->WriteCustomCommandBuildStatement(i->first, ccTargetDeps);
  }
}

std::string cmLocalNinjaGenerator::MakeCustomLauncher(
  cmCustomCommandGenerator const& ccg)
{
  const char* property_value =
    this->Makefile->GetProperty("RULE_LAUNCH_CUSTOM");

  if (!property_value || !*property_value) {
    return std::string();
  }

  // Expand rule variables referenced in the given launcher command.
  cmRulePlaceholderExpander::RuleVariables vars;

  std::string output;
  const std::vector<std::string>& outputs = ccg.GetOutputs();
  if (!outputs.empty()) {
    output = outputs[0];
    if (ccg.GetWorkingDirectory().empty()) {
      output =
        this->ConvertToRelativePath(this->GetCurrentBinaryDirectory(), output);
    }
    output = this->ConvertToOutputFormat(output, cmOutputConverter::SHELL);
  }
  vars.Output = output.c_str();

  std::unique_ptr<cmRulePlaceholderExpander> rulePlaceholderExpander(
    this->CreateRulePlaceholderExpander());

  std::string launcher = property_value;
  rulePlaceholderExpander->ExpandRuleVariables(this, launcher, vars);
  if (!launcher.empty()) {
    launcher += " ";
  }

  return launcher;
}